Displays with viewer tracking

ABSTRACT

An electronic device may include a lenticular display. The lenticular display may have a lenticular lens film formed over an array of pixels. The lenticular lenses may be configured to enable stereoscopic viewing of the display such that a viewer perceives three-dimensional images. The display may have a number of independently controllable viewing zones. A eye and/or head tracking system may use a camera to capture images of a viewer of the display. Control circuitry in the electronic device may use the captured images from the eye and/or head tracking system to determine which viewing zones are occupied by the viewer&#39;s eyes. The control circuitry may disable or dim viewing zones that are not occupied by the viewer&#39;s eyes in order to conserve power. An unoccupied viewing zone and an adjacent, occupied viewing zone may display the same image to increase sharpness in the display.

This application claims the benefit of provisional patent applicationNo. 63/023,479, filed May 12, 2020, which is hereby incorporated byreference herein in its entirety.

FIELD

This relates generally to electronic devices, and, more particularly, toelectronic devices with displays.

BACKGROUND

Electronic devices often include displays. In some cases, displays mayinclude lenticular lenses that enable the display to providethree-dimensional content to the viewer. The lenticular lenses may beformed over an array of pixels such as organic light-emitting diodepixels or liquid crystal display pixels.

SUMMARY

An electronic device may include a lenticular display. The lenticulardisplay may have a lenticular lens film formed over an array of pixels.A plurality of lenticular lenses may extend across the length of thedisplay. The lenticular lenses may be configured to enable stereoscopicviewing of the display such that a viewer perceives three-dimensionalimages.

The electronic device may also include an eye and/or head trackingsystem. The eye and/or head tracking system uses a camera to captureimages of a viewer of the display. The capture images may be used todetermine a viewer's eye position.

The display may have a number of independently controllable viewingzones. Each viewing zone displays a respective two-dimensional image.Each eye of the viewer may receive a different one of thetwo-dimensional images, resulting in a perceived three-dimensionalimage. Control circuitry in the electronic device may use the capturedimages from the eye and/or head tracking system to determine whichviewing zones are occupied by the viewer's eyes.

The control circuitry may disable viewing zones that are not occupied bythe viewer's eyes in order to conserve power. In some cases, the viewingzones may be set to follow a brightness profile that allows power to beconserved while avoiding latency artifacts. The brightness profile maybe a step function or a gaussian function, with unoccupied viewing zonesadjacent to the occupied viewing zones having non-zero brightnesslevels.

Control circuitry may also adjust the display to provide the same imagein different viewing zones. An unoccupied viewing zone and an adjacent,occupied viewing zone may display the same image to increase sharpnessin the display. The display may optionally include a louver film forblocking high angle light.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of an illustrative electronic devicehaving a display in accordance with an embodiment.

FIG. 2 is a top view of an illustrative display in an electronic devicein accordance with an embodiment.

FIG. 3 is a cross-sectional side view of an illustrative lenticulardisplay that provides images to a viewer in accordance with anembodiment.

FIG. 4 is a cross-sectional side view of an illustrative lenticulardisplay that provides images to two or more viewers in accordance withan embodiment.

FIG. 5 is a top view of an illustrative lenticular lens film showing theelongated shape of the lenticular lenses in accordance with anembodiment.

FIG. 6 is a diagram of an illustrative display that includes an eyeand/or head tracking system that determines viewer eye position andcontrol circuitry that updates the display based on the viewer eyeposition in accordance with an embodiment.

FIGS. 7A-7C are perspective views of illustrative three-dimensionalcontent that may be displayed on different zones of the display of FIG.6 in accordance with an embodiment.

FIGS. 8A and 8B are side views of an illustrative display showing howviewing zones may be enabled and disabled based on viewer eye positioninformation in accordance with an embodiment.

FIG. 9A is a side view of an illustrative display with unoccupied zonesthat have brightness levels that follow a step function in accordancewith an embodiment.

FIG. 9B is a graph of an illustrative step function that may be used todetermine zone brightness levels in accordance with an embodiment.

FIG. 10A is a side view of an illustrative display with unoccupied zonesthat have brightness levels that gradually decrease with increasingdistance from the closest occupied zone in accordance with anembodiment.

FIG. 10B is a graph of an illustrative gaussian function that may beused to determine zone brightness levels in accordance with anembodiment.

FIG. 11 is a side view of an illustrative display with images that aremodified based on viewer eye position information in accordance with anembodiment.

FIG. 12 is a side view of an illustrative display showing how asecondary viewing cone may be utilized based on viewer eye positioninformation in accordance with an embodiment.

FIG. 13 is a cross-sectional side view of an illustrative display thatincludes a louver film in accordance with an embodiment.

FIG. 14 is a side view of an illustrative display showing how a louverfilm may be used to block secondary viewing cones in accordance with anembodiment.

FIG. 15 is a flowchart showing illustrative method steps involved inoperating an electronic device with a display and a head tracking systemsuch as the electronic device of FIG. 6 in accordance with anembodiment.

DETAILED DESCRIPTION

An illustrative electronic device of the type that may be provided witha display is shown in FIG. 1 . Electronic device 10 may be a computingdevice such as a laptop computer, a computer monitor containing anembedded computer, a tablet computer, a cellular telephone, a mediaplayer, or other handheld or portable electronic device, a smallerdevice such as a wrist-watch device, a pendant device, a headphone orearpiece device, an augmented reality (AR) headset and/or virtualreality (VR) headset, a device embedded in eyeglasses or other equipmentworn on a user's head, or other wearable or miniature device, a display,a computer display that contains an embedded computer, a computerdisplay that does not contain an embedded computer, a gaming device, anavigation device, an embedded system such as a system in whichelectronic equipment with a display is mounted in a kiosk or automobile,or other electronic equipment.

As shown in FIG. 1 , electronic device 10 may have control circuitry 16.Control circuitry 16 may include storage and processing circuitry forsupporting the operation of device 10. The storage and processingcircuitry may include storage such as hard disk drive storage,nonvolatile memory (e.g., flash memory or otherelectrically-programmable-read-only memory configured to form a solidstate drive), volatile memory (e.g., static or dynamicrandom-access-memory), etc. Processing circuitry in control circuitry 16may be used to control the operation of device 10. The processingcircuitry may be based on one or more microprocessors, microcontrollers,digital signal processors, baseband processors, power management units,audio chips, application specific integrated circuits, etc.

To support communications between device 10 and external equipment,control circuitry 16 may communicate using communications circuitry 21.Circuitry 21 may include antennas, radio-frequency transceivercircuitry, and other wireless communications circuitry and/or wiredcommunications circuitry. Circuitry 21, which may sometimes be referredto as control circuitry and/or control and communications circuitry, maysupport bidirectional wireless communications between device 10 andexternal equipment over a wireless link (e.g., circuitry 21 may includeradio-frequency transceiver circuitry such as wireless local areanetwork transceiver circuitry configured to support communications overa wireless local area network link, near-field communicationstransceiver circuitry configured to support communications over anear-field communications link, cellular telephone transceiver circuitryconfigured to support communications over a cellular telephone link, ortransceiver circuitry configured to support communications over anyother suitable wired or wireless communications link). Wirelesscommunications may, for example, be supported over a Bluetooth® link, aWiFi® link, a 60 GHz link or other millimeter wave link, a cellulartelephone link, or other wireless communications link. Device 10 may, ifdesired, include power circuits for transmitting and/or receiving wiredand/or wireless power and may include batteries or other energy storagedevices. For example, device 10 may include a coil and rectifier toreceive wireless power that is provided to circuitry in device 10.

Input-output circuitry in device 10 such as input-output devices 12 maybe used to allow data to be supplied to device 10 and to allow data tobe provided from device 10 to external devices. Input-output devices 12may include buttons, joysticks, scrolling wheels, touch pads, key pads,keyboards, microphones, speakers, tone generators, vibrators, cameras,sensors, light-emitting diodes and other status indicators, data ports,and other electrical components. A user can control the operation ofdevice 10 by supplying commands through input-output devices 12 and mayreceive status information and other output from device 10 using theoutput resources of input-output devices 12.

Input-output devices 12 may include one or more displays such as display14. Display 14 may be a touch screen display that includes a touchsensor for gathering touch input from a user or display 14 may beinsensitive to touch. A touch sensor for display 14 may be based on anarray of capacitive touch sensor electrodes, acoustic touch sensorstructures, resistive touch components, force-based touch sensorstructures, a light-based touch sensor, or other suitable touch sensorarrangements.

Some electronic devices may include two displays. In one possiblearrangement, a first display may be positioned on one side of the deviceand a second display may be positioned on a second, opposing side of thedevice. The first and second displays therefore may have a back-to-backarrangement. One or both of the displays may be curved.

Sensors in input-output devices 12 may include force sensors (e.g.,strain gauges, capacitive force sensors, resistive force sensors, etc.),audio sensors such as microphones, touch and/or proximity sensors suchas capacitive sensors (e.g., a two-dimensional capacitive touch sensorintegrated into display 14, a two-dimensional capacitive touch sensoroverlapping display 14, and/or a touch sensor that forms a button,trackpad, or other input device not associated with a display), andother sensors. If desired, sensors in input-output devices 12 mayinclude optical sensors such as optical sensors that emit and detectlight, ultrasonic sensors, optical touch sensors, optical proximitysensors, and/or other touch sensors and/or proximity sensors,monochromatic and color ambient light sensors, image sensors,fingerprint sensors, temperature sensors, sensors for measuringthree-dimensional non-contact gestures (“air gestures”), pressuresensors, sensors for detecting position, orientation, and/or motion(e.g., accelerometers, magnetic sensors such as compass sensors,gyroscopes, and/or inertial measurement units that contain some or allof these sensors), health sensors, radio-frequency sensors, depthsensors (e.g., structured light sensors and/or depth sensors based onstereo imaging devices), optical sensors such as self-mixing sensors andlight detection and ranging (lidar) sensors that gather time-of-flightmeasurements, humidity sensors, moisture sensors, gaze tracking sensors,and/or other sensors.

Control circuitry 16 may be used to run software on device 10 such asoperating system code and applications. During operation of device 10,the software running on control circuitry 16 may display images ondisplay 14 using an array of pixels in display 14.

Display 14 may be an organic light-emitting diode display, a liquidcrystal display, an electrophoretic display, an electrowetting display,a plasma display, a microelectromechanical systems display, a displayhaving a pixel array formed from crystalline semiconductorlight-emitting diode dies (sometimes referred to as microLEDs), and/orother display. Configurations in which display 14 is an organiclight-emitting diode display are sometimes described herein as anexample.

Display 14 may have a rectangular shape (i.e., display 14 may have arectangular footprint and a rectangular peripheral edge that runs aroundthe rectangular footprint) or may have other suitable shapes. Display 14may be planar or may have a curved profile.

Device 10 may include cameras and other components that form part ofgaze and/or head tracking system 18. The camera(s) or other componentsof system 18 may face an expected location for a viewer and may trackthe viewer's eyes and/or head (e.g., images and other informationcaptured by system 18 may be analyzed by control circuitry 16 todetermine the location of the viewer's eyes and/or head). Thishead-location information obtained by system 18 may be used to determinethe appropriate direction with which display content from display 14should be directed. Eye and/or head tracking system 18 may include anydesired number/combination of infrared and/or visible light detectors.Eye and/or head tracking system 18 may optionally include light emittersto illuminate the scene.

A top view of a portion of display 14 is shown in FIG. 2 . As shown inFIG. 2 , display 14 may have an array of pixels 22 formed on substrate36. Substrate 36 may be formed from glass, metal, plastic, ceramic, orother substrate materials. Pixels 22 may receive data signals oversignal paths such as data lines D and may receive one or more controlsignals over control signal paths such as horizontal control lines G(sometimes referred to as gate lines, scan lines, emission controllines, etc.). There may be any suitable number of rows and columns ofpixels 22 in display 14 (e.g., tens or more, hundreds or more, orthousands or more). Each pixel 22 may have a light-emitting diode 26that emits light 24 under the control of a pixel circuit formed fromthin-film transistor circuitry (such as thin-film transistors 28 andthin-film capacitors). Thin-film transistors 28 may be polysiliconthin-film transistors, semiconducting-oxide thin-film transistors suchas indium gallium zinc oxide transistors, or thin-film transistorsformed from other semiconductors. Pixels 22 may contain light-emittingdiodes of different colors (e.g., red, green, and blue diodes for red,green, and blue pixels, respectively) to provide display 14 with theability to display color images.

Display driver circuitry may be used to control the operation of pixels22. The display driver circuitry may be formed from integrated circuits,thin-film transistor circuits, or other suitable circuitry. Displaydriver circuitry 30 of FIG. 2 may contain communications circuitry forcommunicating with system control circuitry such as control circuitry 16of FIG. 1 over path 32. Path 32 may be formed from traces on a flexibleprinted circuit or other cable. During operation, the control circuitry(e.g., control circuitry 16 of FIG. 1 ) may supply circuitry 30 withinformation on images to be displayed on display 14.

To display the images on display pixels 22, display driver circuitry 30may supply image data to data lines D while issuing clock signals andother control signals to supporting display driver circuitry such asgate driver circuitry 34 over path 38. If desired, circuitry 30 may alsosupply clock signals and other control signals to gate driver circuitryon an opposing edge of display 14.

Gate driver circuitry 34 (sometimes referred to as horizontal controlline control circuitry) may be implemented as part of an integratedcircuit and/or may be implemented using thin-film transistor circuitry.Horizontal control lines G in display 14 may carry gate line signals(scan line signals), emission enable control signals, and otherhorizontal control signals for controlling the pixels of each row. Theremay be any suitable number of horizontal control signals per row ofpixels 22 (e.g., one or more, two or more, three or more, four or more,etc.).

Display 14 may sometimes be a stereoscopic display that is configured todisplay three-dimensional content for a viewer. Stereoscopic displaysare capable of displaying multiple two-dimensional images that areviewed from slightly different angles. When viewed together, thecombination of the two-dimensional images creates the illusion of athree-dimensional image for the viewer. For example, a viewer's left eyemay receive a first two-dimensional image and a viewer's right eye mayreceive a second, different two-dimensional image. The viewer perceivesthese two different two-dimensional images as a single three-dimensionalimage.

There are numerous ways to implement a stereoscopic display. Display 14may be a lenticular display that uses lenticular lenses (e.g., elongatedlenses that extend along parallel axes), may be a parallax barrierdisplay that uses parallax barriers (e.g., an opaque layer withprecisely spaced slits to create a sense of depth through parallax), maybe a volumetric display, or may be any other desired type ofstereoscopic display. Configurations in which display 14 is a lenticulardisplay are sometimes described herein as an example.

FIG. 3 is a cross-sectional side view of an illustrative lenticulardisplay that may be incorporated into electronic device 10. Display 14includes a display panel 20 with pixels 22 on substrate 36. Substrate 36may be formed from glass, metal, plastic, ceramic, or other substratematerials and pixels 22 may be organic light-emitting diode pixels,liquid crystal display pixels, or any other desired type of pixels.

As shown in FIG. 3 , lenticular lens film 42 may be formed over thedisplay pixels. Lenticular lens film 42 (sometimes referred to as alight redirecting film, a lens film, etc.) includes lenses 46 and a basefilm portion 44 (e.g., a planar film portion to which lenses 46 areattached). Lenses 46 may be lenticular lenses that extend alongrespective longitudinal axes (e.g., axes that extend into the pageparallel to the Y-axis). Lenses 46 may be referred to as lenticularelements 46, lenticular lenses 46, optical elements 46, etc.

The lenses 46 of the lenticular lens film cover the pixels of display14. An example is shown in FIG. 3 with display pixels 22-1, 22-2, 22-3,22-4, 22-5, and 22-6. In this example, display pixels 22-1 and 22-2 arecovered by a first lenticular lens 46, display pixels 22-3 and 22-4 arecovered by a second lenticular lens 46, and display pixels 22-5 and 22-6are covered by a third lenticular lens 46. The lenticular lenses mayredirect light from the display pixels to enable stereoscopic viewing ofthe display.

Consider the example of display 14 being viewed by a viewer with a firsteye (e.g., a right eye) 48-1 and a second eye (e.g., a left eye) 48-2.Light from pixel 22-1 is directed by the lenticular lens film indirection 40-1 towards left eye 48-2, light from pixel 22-2 is directedby the lenticular lens film in direction 40-2 towards right eye 48-1,light from pixel 22-3 is directed by the lenticular lens film indirection 40-3 towards left eye 48-2, light from pixel 22-4 is directedby the lenticular lens film in direction 40-4 towards right eye 48-1,light from pixel 22-5 is directed by the lenticular lens film indirection 40-5 towards left eye 48-2, light from pixel 22-6 is directedby the lenticular lens film in direction 40-6 towards right eye 48-1. Inthis way, the viewer's right eye 48-1 receives images from pixels 22-2,22-4, and 22-6, whereas left eye 48-2 receives images from pixels 22-1,22-3, and 22-5. Pixels 22-2, 22-4, and 22-6 may be used to display aslightly different image than pixels 22-1, 22-3, and 22-5. Consequently,the viewer may perceive the received images as a singlethree-dimensional image.

Pixels of the same color may be covered by a respective lenticular lens46. In one example, pixels 22-1 and 22-2 may be red pixels that emit redlight, pixels 22-3 and 22-4 may be green pixels that emit green light,and pixels 22-5 and 22-6 may be blue pixels that emit blue light. Thisexample is merely illustrative. In general, each lenticular lens maycover any desired number of pixels each having any desired color. Thelenticular lens may cover a plurality of pixels having the same color,may cover a plurality of pixels each having different colors, may covera plurality of pixels with some pixels being the same color and somepixels being different colors, etc.

FIG. 4 is a cross-sectional side view of an illustrative stereoscopicdisplay showing how the stereoscopic display may be viewable by multipleviewers. The stereoscopic display of FIG. 3 may have one optimal viewingposition (e.g., one viewing position where the images from the displayare perceived as three-dimensional). The stereoscopic display of FIG. 4may have two or more optimal viewing positions (e.g., two or moreviewing positions where the images from the display are perceived asthree-dimensional).

Display 14 may be viewed by both a first viewer with a right eye 48-1and a left eye 48-2 and a second viewer with a right eye 48-3 and a lefteye 48-4. Light from pixel 22-1 is directed by the lenticular lens filmin direction 40-1 towards left eye 48-4, light from pixel 22-2 isdirected by the lenticular lens film in direction 40-2 towards right eye48-3, light from pixel 22-3 is directed by the lenticular lens film indirection 40-3 towards left eye 48-2, light from pixel 22-4 is directedby the lenticular lens film in direction 40-4 towards right eye 48-1,light from pixel 22-5 is directed by the lenticular lens film indirection 40-5 towards left eye 48-4, light from pixel 22-6 is directedby the lenticular lens film in direction 40-6 towards right eye 48-3,light from pixel 22-7 is directed by the lenticular lens film indirection 40-7 towards left eye 48-2, light from pixel 22-8 is directedby the lenticular lens film in direction 40-8 towards right eye 48-1,light from pixel 22-9 is directed by the lenticular lens film indirection 40-9 towards left eye 48-4, light from pixel 22-10 is directedby the lenticular lens film in direction 40-10 towards right eye 48-3,light from pixel 22-11 is directed by the lenticular lens film indirection 40-11 towards left eye 48-2, and light from pixel 22-12 isdirected by the lenticular lens film in direction 40-12 towards righteye 48-1. In this way, the first viewer's right eye 48-1 receives imagesfrom pixels 22-4, 22-8, and 22-12, whereas left eye 48-2 receives imagesfrom pixels 22-3, 22-7, and 22-11. Pixels 22-4, 22-8, and 22-12 may beused to display a slightly different image than pixels 22-3, 22-7, and22-11. Consequently, the first viewer may perceive the received imagesas a single three-dimensional image. Similarly, the second viewer'sright eye 48-3 receives images from pixels 22-2, 22-6, and 22-10,whereas left eye 48-4 receives images from pixels 22-1, 22-5, and 22-9.Pixels 22-2, 22-6, and 22-10 may be used to display a slightly differentimage than pixels 22-1, 22-5, and 22-9. Consequently, the second viewermay perceive the received images as a single three-dimensional image.

Pixels of the same color may be covered by a respective lenticular lens46. In one example, pixels 22-1, 22-2, 22-3, and 22-4 may be red pixelsthat emit red light, pixels 22-5, 22-6, 22-7, and 22-8 may be greenpixels that emit green light, and pixels 22-9, 22-10, 22-11, and 22-12may be blue pixels that emit blue light. This example is merelyillustrative. The display may be used to present the samethree-dimensional image to both viewers or may present differentthree-dimensional images to different viewers. In some cases, controlcircuitry in the electronic device 10 may use eye and/or head trackingsystem 18 to track the position of one or more viewers and displayimages on the display based on the detected position of the one or moreviewers.

It should be understood that the lenticular lens shapes and directionalarrows of FIGS. 3 and 4 are merely illustrative. The actual rays oflight from each pixel may follow more complicated paths (e.g., withredirection occurring due to refraction, total internal reflection,etc.). Additionally, light from each pixel may be emitted over a rangeof angles. The lenticular display may also have lenticular lenses of anydesired shape or shapes. Each lenticular lens may have a width thatcovers two pixels, three pixels, four pixels, more than four pixels,more than ten pixels, etc. Each lenticular lens may have a length thatextends across the entire display (e.g., parallel to columns of pixelsin the display).

FIG. 5 is a top view of an illustrative lenticular lens film that may beincorporated into a lenticular display. As shown in FIG. 5 , elongatedlenses 46 extend across the display parallel to the Y-axis. For example,the cross-sectional side view of FIGS. 3 and 4 may be taken looking indirection 50. The lenticular display may include any desired number oflenticular lenses 46 (e.g., more than 10, more than 100, more than1,000, more than 10,000, etc.). In FIG. 5 , the lenticular lenses extendperpendicular to the upper and lower edge of the display panel. Thisarrangement is merely illustrative, and the lenticular lenses mayinstead extend at a non-zero, non-perpendicular angle (e.g., diagonally)relative to the display panel if desired.

FIG. 6 is a schematic diagram of an illustrative electronic deviceshowing how information from eye and/or head tracking system 18 may beused to control operation of the display. As shown in FIG. 6 , display14 is capable of providing unique images across a number of distinctzones. In FIG. 6 , display 14 emits light across 14 zones, each having arespective angle of view 52. The angle 52 may be between 1° and 2°,between 0° and 4°, less than 5°, less than 3°, less than 2°, less than1.5°, greater than 0.5°, or any other desired angle. Each zone may havethe same associated viewing angle or different zones may have differentassociated viewing angles.

The example herein of the display having 14 independently controllablezones is merely illustrative. In general, the display may have anydesired number of independently controllable zones (e.g., more than 2,more than 6, more than 10, more than 12, more than 16, more than 20,more than 30, more than 40, less than 40, between 10 and 30, between 12and 25, etc.).

Each zone is capable of displaying a unique image to the viewer. Thesub-pixels on display 14 may be divided into groups, with each group ofsub-pixels capable of displaying an image for a particular zone. Forexample, a first subset of sub-pixels in display 14 is used to displayan image (e.g., a two-dimensional image) for zone 1, a second subset ofsub-pixels in display 14 is used to display an image for zone 2, a thirdsubset of sub-pixels in display 14 is used to display an image for zone3, etc. In other words, the sub-pixels in display 14 may be divided into14 groups, with each group associated with a corresponding zone(sometimes referred to as viewing zone) and capable of displaying aunique image for that zone. The sub-pixel groups may also themselves bereferred to as zones.

Control circuitry 16 may control display 14 to display desired images ineach viewing zone. There is much flexibility in how the display providesimages to the different viewing zones. Display 14 may display entirelydifferent content in different zones of the display. For example, animage of a first object (e.g., a cube) is displayed for zone 1, an imageof a second, different object (e.g., a pyramid) is displayed for zone 2,an image of a third, different object (e.g., a cylinder) is displayedfor zone 3, etc. This type of scheme may be used to allow differentviewers to view entirely different scenes from the same display.However, in practice there may be crosstalk between the viewing zones.As an example, content intended for zone 3 may not be contained entirelywithin viewing zone 3 and may leak into viewing zones 2 and 4.

Therefore, in another possible use-case, display 14 may display asimilar image for each viewing zone, with slight adjustments forperspective between each zone. This may be referred to as displaying thesame content at different perspectives, with one image corresponding toa unique perspective of the same content. For example, consider anexample where the display is used to display a three-dimensional cube.The same content (e.g., the cube) may be displayed on all of thedifferent zones in the display. However, the image of the cube providedto each viewing zone may account for the viewing angle associated withthat particular zone. In zone 1, for example, the viewing cone may be ata −10° angle relative to the surface normal of the display. Therefore,the image of the cube displayed for zone 1 may be from the perspectiveof a −10° angle relative to the surface normal of the cube (as in FIG.7A). Zone 7, in contrast, is at approximately the surface normal of thedisplay. Therefore, the image of the cube displayed for zone 7 may befrom the perspective of a 0° angle relative to the surface normal of thecube (as in FIG. 7B). Zone 14 is at a 10° angle relative to the surfacenormal of the display. Therefore, the image of the cube displayed forzone 14 may be from the perspective of a 100 angle relative to thesurface normal of the cube (as in FIG. 7C). As a viewer progresses fromzone 1 to zone 14 in order, the appearance of the cube gradually changesto simulate looking at a real-world object.

There are many possible variations for how display 14 displays contentfor the viewing zones. In general, each viewing zone may be providedwith any desired image based on the application of the electronicdevice. Different zones may provide different images of the same contentat different perspectives, different zones may provide different imagesof different content, etc.

In one possible scenario, display 14 may display images for all of theviewing zones at the same time. However, this requires emitting lightwith all of the sub-pixels in the display in order to generate imagesfor each viewing zone. Simultaneously providing images for all of theviewing zones at the same time therefore may consume more power than isdesired. To reduce power consumption in the display, one or more of thezones may be disabled based on information from the eye and/or headtracking system 18.

Eye and/or head tracking system 18 (sometimes referred to as viewertracking system 18, head tracking system 18, or tracking system 18) mayuse one or more cameras such as camera 54 to capture images of the areain front of the display 14 where a viewer is expected to be present. Thetracking system may use the captured images to identify a position ofthe viewer relative to the viewing zones. In other words, the trackingsystem may be used to determine which viewing zone(s) the viewer isoccupying. Each eye of the user may be associated with a differentviewing zone (in order to allow three-dimensional content to beperceived by the user from the display). Based on the captured images,tracking system 18 may identify a first viewing zone associated with aleft eye of the viewer and a second viewing zone associated with a righteye of the viewer. Tracking system 18 may use one camera, two cameras,three cameras, more than three cameras, etc. to obtain information onthe position of the viewer(s). The cameras in the tracking system maycapture visible light and/or infrared light images.

Control circuitry 16 may use information from tracking system 18 toselectively disable unoccupied viewing zones. Disabling unoccupiedviewing zones conserves power within the electronic device. Controlcircuitry 16 may receive various types of information from trackingsystem 18 regarding the position of the viewer. Control circuitry 16 mayreceive raw data from head tracking system 18 and process the data todetermine the position of a viewer, may receive position coordinatesfrom head tracking system 18, may receive an identification of one ormore occupied viewing zones from head tracking system 18, etc. If headtracking system 18 includes processing circuitry configured to processdata from the one or more cameras to determine the viewer position, thisportion of the head tracking system may also be considered controlcircuitry (e.g., control circuitry 16). Control circuitry 16 may includea graphics processing unit (GPU) that generates image data to bedisplayed on display 14. The GPU may generate image data based on theviewer position information.

In general, electronic device 10 includes one or more cameras 54 forcapturing images of an environment around the display (e.g., an area infront of the display where viewers are expected to be located). Controlcircuitry within the electronic device uses the images from the one ormore cameras to identify which viewing zones are occupied by the viewer.The control circuitry then controls the display accordingly based on theoccupied viewing zones.

FIGS. 8A and 8B are diagrams illustrating how viewing zones may bedisabled to reduce power consumption in the electronic device. As shownin FIG. 8A, display 14 is being viewed by a viewer with a first eye(e.g., a right eye) 48-1 and a second eye (e.g., a left eye) 48-2. Thefirst eye 48-1 is in viewing zone 3 whereas the second eye is present inviewing zone 5.

A camera in head tracking system 18 may capture an image of the viewerand identify the location of eyes 48-1 and 48-2. Accordingly, controlcircuitry in the electronic device may determine that the user's eyesare present in viewing zones 3 and 5. In response, the control circuitrycontrols display 14 to display the desired images in viewing zones 3 and5. However, the other viewing zones (e.g., zones 1, 2, 4, and 6-14) aredisabled. In other words, the sub-pixels of the other zones are turnedoff so that they do not emit light and do not consume power. This savespower consumption within the electronic device while providing asatisfactory user experience with the active zones 3 and 5. The zoneswhere light is emitted (e.g., zones 3 and 5 in FIG. 8A) may sometimes bereferred to as active zones, enabled zones, zones that are ‘on’, or litzones. The zones where light is not emitted (e.g., zones 1, 2, 4, and6-14 in FIG. 8A) may sometimes be referred to as inactive zones,disabled zones, zones that are ‘off’, or unlit zones.

The active zones may be updated based on the real-time position of theviewer. For example, the viewer may shift in direction 56 as shown inFIG. 8A. After shifting positions, the viewer may end up in the positionshown in FIG. 8B. Eye 48-1 is now aligned with zone 4 and eye 48-2 isnow aligned with zone 6. Tracking system 18 may identify this shift inposition based on images captured of the viewer. In response to theposition change, control circuitry 16 updates display 14 to turn onzones 4 and 6 and turn off the remaining zones (zones 1-3, 5, and 7-14),as shown in FIG. 8B. In this way, control circuitry 16 may continuallyupdate display 14 to activate only the zones where the viewer's eyes arepresent and disable the remaining zones.

Ideally, tracking system 18 would always quickly and accurately identifythe position of the viewer. This information would then be used by thecontrol circuitry to update the display in real time, such that theactivated viewing zones always align with the viewer's eyes. Inpractice, however, there may be latency between a viewer changingposition and the display being updated accordingly. If the user changesposition quickly, they may move into an inactive zone and the displaywill appear dark (off) until the display updates. In other scenarios,due to a variety of possible factors the tracking system 18 may lose theposition of the viewer in the scene. This is sometimes referred to astracking loss. If tracking loss occurs, the viewer may shift position toa new viewing zone without being detected by the tracking system. Thisagain may result in the viewer shifting to a position where the displayappears to be dark (even though the display should be showing content tothe user).

To prevent visible artifacts caused by latency and/or tracking loss, thedisplay may emit light for viewing zones that are not occupied. FIG. 9Ais a diagram showing a display emitting light at full brightness inseveral unoccupied viewing zones. In the example of FIG. 9A, eye 48-1 isin zone 4 and eye 48-2 is in zone 6. These zones therefore have fullbrightness (e.g., 100% brightness as indicated in FIG. 9A). However,some of the adjacent zones to zones 4 and 6 also have full brightnesseven though they are currently unoccupied by a viewer. As shown in FIG.9A, zones, 2, 3, 5, 7, and 8 are enabled (e.g., operating at 100%brightness). Zones 1 and 9-14 remain disabled (e.g., turned off at 0%brightness).

The arrangement of FIG. 9A may mitigate visible artifacts for the viewerwhen the viewer shifts positions to adjacent viewing zones. For example,in FIG. 9A the viewer may shift to their right, resulting in eye 48-1occupying viewing zone 3 and eye 48-2 occupying viewing zone 5. Due totracking latency, electronic device 10 may not recognize and updatedisplay 14 based on this shift for some length of time. If zones 1-3, 5,and 7-14 are all turned off (e.g., as in FIG. 8B), the display appearsdark for the viewer during the entirety of the latency time. With thescheme of FIG. 9A, however, the viewer still perceives the content onthe display correctly during the latency time due to zones 3 and 5already being at 100% brightness.

It should be noted that each zone may have a corresponding image. Asshown in FIG. 9A, zone 1 displays image A, zone 2 displays image B, zone3 displays image C, . . . , zone 14 displays image N. The image of eachzone may be unique (e.g., tailored to the particular perspectiveassociated with that viewing zone). In this example, the images A-N mayall be associated with the same content (at unique perspectives). Inthis way, the viewer may shift position while the three-dimensionalimage appears as a stationary, real-life object. This example is merelyillustrative and other images may be used for images A-N if desired.

Because zones 3 and 5 are displaying images C and E at full brightness,if the user shifts position to zones 3 and 5 they will immediatelyperceive the images C and E (which have the correct perspective forthose positions) without waiting for the display to update. Therefore,the user may seamlessly transition between viewing zones without visibleartifacts caused by latency, loss of viewer tracking capabilities, etc.

In FIG. 9A, the brightness of the viewing zones follows a step-functionrelative to the occupied viewing zones. In other words, each occupiedviewing zone (zones 4 and 6 in FIG. 9A) has two adjacent viewing zoneson either side that are also provided at full brightness. For example,zones 7 and 8 to the right of zone 6 are provided at full brightness andzones 2 and 3 to the left of zone 4 are provided at full brightness.Past these zones, however, the brightness drops to 0% (e.g., the zonesare disabled). This example is merely illustrative. In another example,only one adjacent viewing zone on either side of the occupied viewingzone may operate at full brightness.

FIG. 9B is a graph of an illustrative brightness profile that may beused for the display zones. As shown in FIG. 9B, there may be a zoneZ_(n) where the viewer's eye is located. Zones are present on eitherside of zone Z_(n) (e.g., Z_(n−1), Z_(n−2), Z_(n−3), Z_(n+1), Z_(n+2),Z_(n+3), etc.). In FIG. 9B, the brightness at zone Z₁ is BR1. This maybe 100% (e.g., the maximum brightness the display is capable of) or someother desired peak brightness (e.g., a brightness determined to beappropriate for the real time lighting conditions of the display). Forexample, in dim ambient light conditions BR1 may be less than themaximum brightness the display is capable of. BR1 may be referred to asa full brightness level.

In FIG. 9B, two zones adjacent to Z₁ have the same brightness as Z_(n).Zones Z_(n+1), Z_(n+2), Z_(n−1), and Z_(n−2) all have the samebrightness BR1 as Z_(n). Past this point, however, the brightness dropsto BR2 (e.g., 0% or off). As shown in FIG. 9B, zones that are 3 or morezones away from the zone including the viewer's eye may be operated atlower brightness level BR2.

Of course, the viewer's second eye may be present in a zone near theviewer's first eye. Unoccupied zones that are interposed between twoeyes may have a brightness dictated by the dimming profile for thecloser eye, may have the highest brightness of the two magnitudesassociated with each respective eye's brightness profile, etc. Thenumber of unoccupied zones between a user's eyes may depend upon theparticular display design, the distance of the user from the display,etc. Therefore, for simplicity, the zone brightness profiles (as in FIG.9B) are characterized relative to a single zone (e.g., Z_(n) in FIG. 9B)associated with a single eye.

The specific characteristics of the brightness profile of FIG. 9B may betuned based on the desired power consumption savings, viewer experience,and other factors associated with a particular electronic device design.In general, having more unoccupied zones enabled and having higherbrightness levels within each unoccupied zone is optimal for a user'sviewing experience (as artifacts will be minimal even if there islatency or tracking loss). Having fewer unoccupied zones enabled andhaving lower brightness levels within each unoccupied zone is optimalfor reducing power consumption. These tradeoffs may be balanced for eachdesign, may be adjusted by a user of the electronic device, may beadjusted based on other factors (e.g., ambient light conditions), etc.

In other words, the number of adjacent zones on either side of Z₁ inFIG. 9B at brightness BR1 may be 0, 1, 2 (as in FIG. 9B), 3, 4, morethan 4, more than 2, between 1 and 5, etc. The brightness level BR1 maybe 100% or less than 100%. Brightness level BR2 may be 0% or greaterthan 0%.

In the step function of FIG. 9B, zones are placed in one of two states(e.g., the on state at 100% brightness or the off state at 0%brightness). This example is merely illustrative. In another possiblebrightness scheme, the brightness may be gradually lowered in unoccupiedzones adjacent to the occupied zones. The further away an unoccupiedzone is from an occupied zone, the less likely it is that the viewerwill reach that zone without the gaze tracker identifying the shift inposition and updating the display accordingly. Accordingly, havingfurther away unoccupied zones at high brightness levels is lessimportant than close unoccupied zones. The brightness levels of theunoccupied zones may therefore be decreased gradually with increasingdistance from the occupied zones.

As shown in FIG. 10A, eye 48-1 is in zone 4 and eye 48-2 is in zone 6.These zones therefore have full brightness (e.g., 100% brightness asindicated in FIG. 10A). With increasing distance from zone 6, thebrightness level of the unoccupied zones drops. Zone 7 has a brightnesslevel of 90%, zone 8 has a brightness level of 70%, and zone 9 has abrightness level of 40%. Further than zone 9 (e.g., zones 10-14), theunoccupied zones have a brightness level of 0%. The same brightnessdistribution is used adjacent to occupied zone 4 as well. Zone 3 has abrightness level of 90%, zone 2 has a brightness level of 70%, and zone1 has a brightness level of 40%.

FIG. 10B is a graph of an illustrative brightness profile that may beused for the display zones. As shown in FIG. 10B, there may be a zone Z₁where the viewer's eye is located. Zones are present on either side ofzone Z_(n) (e.g., Z_(n−1), Z_(n−2), Z_(n−3), Z_(n+1), Z_(n+2), Z_(n+3),etc.). In FIG. 10B, the brightness at zone Z₁ is BR1. This may be 100%(e.g., the maximum brightness the display is capable of) or some otherdesired peak brightness (e.g., a brightness determined to be appropriatefor the real time lighting conditions of the display).

To either side of the occupied zone Z_(n), the brightness decreases withincreasing distance from zone Z_(n). As shown, a brightness level of BR3may be used one zone from the occupied zone (e.g., zones Z_(n−1) andZ_(n+1)), a brightness level of BR4 may be used two zones from theoccupied zone (e.g., zones Z_(n−2) and Z_(n+2)), a brightness level ofBR5 may be used three zones from the occupied zone (e.g., zones Z_(n−3)and Z_(n+3)), and a brightness level of BR2 may be used more than threezones from the occupied zone (e.g., zones Z_(n−4) and Z_(n+4)). In FIG.10A, BR1 is 100%, BR2 is 0%, BR3 is 90%, BR4 is 70%, and BR5 is 40%.

This example is merely illustrative. Brightness levels BR1-BR5 may haveany desired magnitudes. The brightness level BR1 may be 100% or lessthan 100%. Brightness level BR2 may be 0% or greater than 0%. Ingeneral, the brightness level may gradually decrease with increasingdistance from the closest occupied zone. The brightness level maydecrease monotonically with increasing distance from the closet occupiedzone (as in FIG. 10B). At least one intermediate brightness level may beused between the peak brightness level (of the occupied zone) and theminimum brightness level (e.g., 0%). The brightness level may follow aprofile having any desired shape (e.g., a gaussian profile).

In addition to using information from eye and/or head tracking system 18to reduce power consumption, information from eye and/or head trackingsystem 18 may be used to increase sharpness in the display. FIG. 11shows an arrangement of this type. In FIG. 11 , similar to as shown inFIG. 10A, eye 48-1 is in zone 4 and eye 48-2 is in zone 6. Image D ispresented in zone 4 and image F is presented in zone 6.

As previously mentioned, an image intended for a given viewing area maynot be contained exclusively to that viewing zone. Crosstalk may occurbetween viewing zones within the display. To mitigate crosstalk, theimages for unoccupied zones may be modified based on the viewer eyeposition. In FIG. 11 , unoccupied zones 2 and 3 may display the sameimage as occupied zone 4 (image D). Consequently, if part of the zone 2or zone 3 light leaks into zone 4, the light will correspond to the sameimage as in zone 4. This increases the perceived sharpness of thedisplay to the viewer. Also in FIG. 11 , unoccupied zones 7 and 8 maydisplay the same image as occupied zone 6 (image F). Consequently, ifpart of the zone 7 or zone 8 light leaks into zone 6, the light willcorrespond to the same image as in zone 6.

In FIG. 11 , each of zones 2-8 may emit light with full brightness(e.g., 100% brightness) and each of zones 1 and 9-14 may be turned off(e.g., 0% brightness). The unoccupied zones therefore follow abrightness profile similar to the step function of FIGS. 9A and 9B. Thisexample is merely illustrative. If desired, a gradual brightnessreduction scheme similar to as shown in FIGS. 10A and 10B may be used inFIG. 11 .

A similar concept as in FIG. 11 may be used to improve viewing at highviewing angles. FIG. 12 shows a display of this type. In FIGS. 6-11 ,display 14 is depicted as having fourteen distinct viewing zones thatare each capable of displaying a respective unique image. Outside of thefourteen viewing zones, no additional viewing zones are shown. However,in some cases, a duplicate viewing zone may be present on one or bothsides of the primary viewing zone.

For example, as shown in FIG. 12 , there may be a primary viewing conethat includes zones 1A-14A. FIG. 12 shows an illustrative viewing plane154. The center of the primary viewing cone is orthogonal to the surfaceof display 14. The viewing zones 1A-14A may be referred to as primaryviewing zones. In addition, there may be a secondary viewing cone thatis adjacent to the primary viewing cone and at an angle relative to thedisplay. The secondary viewing cone includes zones 1B-14B. The viewingzones 1B-14B may be referred to as secondary viewing zones. Eachsecondary viewing zone is a duplicate of a primary viewing zone. Forexample, secondary viewing zone 1B displays the same image as primaryviewing zone 1A, secondary viewing zone 2B displays the same image asprimary viewing zone 2A, etc. The images displayed in the secondaryviewing zones 1B-14B may be dimmer versions of the images displayed inprimary viewing zones 1A-14A.

As shown in FIG. 12 , the secondary viewing cone may at least partiallyoverlap the primary viewing cone. Specifically, secondary viewing zone1B overlaps with primary viewing zone 13A and secondary viewing zone 2Boverlaps with primary viewing zone 14A. In some cases, this overlap maylead to undesirable cross-talk. However, using head tracking system 18,the known position of the viewer may be used to improve sharpness of thedisplay.

In FIG. 12 , eye 48-1 is in zone 12A and eye 48-2 is in zone 14A. Eye48-1 may be intended to view image L from zone 12A and eye 48-2 may beintended to view image N from zone 14A. To improve sharpness, theadjacent, non-occupied zones may be modified to display the same imageas the occupied zones. For example, zone 11A may display the same imageas occupied zone 12A (image L). Consequently, if part of the zone 11Alight leaks into zone 12A, the light will correspond to the same imageas in zone 12A.

Zone 14A may display image N. Accordingly, zones 3A and 4A may also beused to display image N. This causes adjacent, non-occupied secondaryzones 3B and 4B to display image N, improving the sharpness of thedisplay. Similarly, zone 2A may be used to display image N. Thesecondary zone 2B that is a duplicate of zone 2A overlaps primary zone14A. Displaying image N in zone 2A therefore ensures that image N isalso displayed in zone 2B (which overlaps primary zone 14A alsodisplaying image N). If zone 2A displayed a different image (e.g., imageB), then a combination of image N and image B would be perceived by eye48-2, resulting in an unclear image.

To summarize, secondary viewing zones may be leveraged to improve thesharpness of the display when head tracking indicates the viewer isviewing from a high viewing angle as in FIG. 12 .

Although in some cases the secondary viewing zones may be utilized toimprove the display, in other cases the secondary viewing zones mayresult in undesirable crosstalk. To block crosstalk of this type, alouver film may optionally be incorporated into the display. FIG. 13 isa cross-sectional side view of a lenticular display with a louver film.As shown in FIG. 13 , louver film 112 may be interposed between displaypanel 20 and lenticular lens film 42. The louver film may block lightpast certain viewing angles. This ensures that light corresponding tothe optimal viewing angle is still emitted from the display (e.g., lightfor the primary cone and zones 1A-14A in FIG. 12 ). However, lightoutside of this area (e.g., light for the secondary viewing cones suchas zones 1B-14B in FIG. 12 ) is blocked by louver film 112. Outside ofthe optimal field of view, the display will simply appear dark (off).

As shown in FIG. 13 , display 14 includes pixels 22 on substrate 36.Substrate 36 may be formed from glass, metal, plastic, ceramic, or othersubstrate materials and pixels 22 may be organic light-emitting diodepixels, liquid crystal display pixels, or any other desired type ofpixels. Lenticular lens film 42 may be formed over the display pixels.Lenticular lens film 42 includes lenses 46 and a base film portion 44.

The display of FIG. 13 also includes a polarizer 122 formed over displaypixels 22. Polarizer 122 may be a linear polarizer (e.g., formed fromlayers of polyvinyl alcohol (PVA) and tri-acetate cellulose (TAC) orformed from other desired materials). Louver film 112 is interposedbetween polarizer 122 and lenticular lens film 42. The louver filmincludes both transparent portions 118 and opaque portions 120. Thetransparent portions of the louver film may be formed from a polymermaterial such as polycarbonate (PC), poly(methyl methacrylate) (PMMA),polyethylene terephthalate (PET), etc. The transparent portions of thelouver film may be formed from other materials such as glass if desired.The transparent portions of the louver film may transmit more than 90%of light, more than 95% of light, more than 99% of light, etc.

Opaque portions 120 of the louver film may be formed from an opaquematerial. For example, the opaque portions may transmit less than 50% oflight, less than 40% of light, less than 30% of light, less than 20% oflight, less than 10% of light, less than 5% of light, less than 1% oflight, etc. The opaque portions may be formed from an opaque polymermaterial or an opaque material of another type. The opaque portions mayextend from an upper surface of the louver film to a lower surface ofthe louver film. Opaque portions 120 may sometimes be referred to asopaque walls. The opaque portions may be elongated parallel to theY-axis, similar to the pattern for the lenticular lenses shown in FIG. 5. Each opaque portion may extend in the Y-direction across the entiredisplay. In the event that the lenticular lenses extend diagonallyacross the display, the opaque walls may also extend diagonally parallelto the lenticular lenses.

Due to the presence of opaque portions 120, the angle of light emittedthrough transparent portions 118 is limited. The angle of emissionthrough the louver film may be less than ±10°, less than ±15°, less than±20°, less than ±30°, less than ±40°, between ±10° and ±30°, between±10° and ±20°, etc. Because louver film 112 reduces theangle-of-emission and accordingly the viewing angle of the display,louver film 112 may sometimes be referred to as an angle-of-emissionreduction layer 112, a viewing angle reduction layer 112, an emissionangle reduction layer 112, etc. The louver film may also be referred toas privacy film 112.

The angle-of-emission reduction layer 112 shown in FIG. 13 is merelyillustrative. Other arrangements may be used for the angle-of-emissionreduction layer. For example, opaque portions 120 may be selectivelyopaque. The opaque portions 120 may optionally be switched between atransparent state and an opaque state. The opaque portions may only havetwo states (e.g., fully transparent and fully opaque) or may haveadditional states between the two extremes if desired. To switch thetransparency of selectively opaque portions 120, control circuitry 16may apply signals to contact 124 and/or contact 126. In one example,opaque portions 120 may be formed from a liquid crystal material.Control circuitry 16 may apply different voltages to electrodes oneither side of the opaque portion (e.g., at contacts 124 and 126) tocontrol the transparency of the opaque portions. In another example, theopaque portions may include electronic ink (e.g., negatively andpositively charged black and white particles that are suspended in aclear fluid). Control circuitry may apply signals to contact 124 and/orcontact 126 to change the opacity of selectively opaque portion 120 tocontrol the emission angle of the display. This example is merelyillustrative. The opacity of opaque portions 120 may be static insteadof switchable if desired.

In another possible arrangement for the angle-of-emission reductionlayer 112, the opaque walls may be incorporated into the base 44 of film42. In yet another possible arrangement, lenticular lens film 46 may beinterposed between display panel 20 and the angle-of-emission reductionlayer 112 (e.g., the position of the lenticular lenses 46 and layer 112may be flipped).

FIG. 14 is a diagram showing how the privacy film may be used to blocksecondary viewing cones in the display. As shown in FIG. 14 , thesecondary viewing cones 130B and 130C may be blocked by the opaque wallsin louver film 112 in the display. The primary viewing cone (with zones1A-14A) remains unblocked and available to present images to one or moreviewers.

The louver film may block the secondary viewing cones when two viewersare viewing the display. Consider a scenario where a first viewer has afirst eye 48-1 in zone 2A and a second eye 48-2 in zone 4A. A secondviewer simultaneously has a first eye 48-3 in zone 10A and a second eye48-4 in zone 12A. When there are two simultaneous viewers of thedisplay, the louver film 112 is helpful for reducing crosstalk.

However, in another scenario, there may only be one viewer present witheyes 48-5 and 48-6 at a high viewing angle. In this type of scenario,the louver film 112 prevents light from reaching eyes 48-5 and 48-6. Ifthe louver film 112 is switchable, the louver film may be switched to atransparent mode when there is a viewer at a high viewing angle.

When the display is updated based on the detected position of theviewer, changes may optionally be made gradually. For example, viewingzones that are turned on and off may fade in and fade out to avoidvisible flickering. The control circuitry may gradually transition azone between two desired brightness levels any time the brightness levelchanges.

FIG. 15 is a flowchart of illustrative method steps for operating anelectronic device of the type shown in FIG. 6 . At step 142, a camera(e.g., camera 54 in eye and/or head tracking system 18) may be used tocapture images of an environment around the electronic display. Inparticular, the camera may capture images of an area in front of thedisplay where a viewer of the display is expected to be present. Theviewer of the display may be expected at distances greater than 1 footfrom the display, greater than 2 feet from the display, greater than 3feet from the display, greater than 5 feet from the display, greaterthan 10 feet from the display, etc.

At step 144, the position of one or more viewers of the display may bedetermined. Control circuitry such as control circuitry 16 may use thecaptured images from the camera to determine how many viewers arepresent and the positions of the viewers. Based on the captured images,the control circuitry may determine in which viewing zone each viewereye is located. The gaze direction of the viewer need not be determinedto identify which viewing zones the viewer eyes are located in. In otherwords, control circuitry 16 may, in some cases, use only the determinedposition of the user's eyes (e.g., in a plane in front of the display)for subsequent processing, and not the direction-of-gaze of the user'seyes.

Finally, at step 146, based on the determined positions of the viewer,the brightness of one or more zones and/or the image displayed by one ormore zones may be updated. FIGS. 8A and 8B show how unoccupied zones maybe turned off. FIGS. 9A-10B show how zone brightness levels may bemodified based on viewer eye position to preserve power while avoidinglatency artifacts. FIGS. 11 and 12 show examples where the images forone or more zones may be updated based on the determined viewer eyepositions to increase display sharpness. In embodiments where thedisplay includes a switchable louver film, the louver film may beswitched between a transparent state and opaque state based on theidentified viewer eye positions. For example, the control circuitry 16may place the louver film in the opaque state when one or more viewersare present in a primary (on-axis) viewing position. The controlcircuitry 16 may place the louver film in the transparent state when oneor more viewers are present in a high viewing angle position. Thecontrol circuitry 16 may gradually transition between brightness levelswhen switching brightness levels.

As described above, one aspect of the present technology is thegathering and use of information such as sensor information. The presentdisclosure contemplates that in some instances, data may be gatheredthat includes personal information data that uniquely identifies or canbe used to contact or locate a specific person. Such personalinformation data can include demographic data, location-based data,telephone numbers, email addresses, twitter ID's, home addresses, dataor records relating to a user's health or level of fitness (e.g., vitalsigns measurements, medication information, exercise information), dateof birth, username, password, biometric information, or any otheridentifying or personal information.

The present disclosure recognizes that the use of such personalinformation, in the present technology, can be used to the benefit ofusers. For example, the personal information data can be used to delivertargeted content that is of greater interest to the user. Accordingly,use of such personal information data enables users to calculatedcontrol of the delivered content. Further, other uses for personalinformation data that benefit the user are also contemplated by thepresent disclosure. For instance, health and fitness data may be used toprovide insights into a user's general wellness, or may be used aspositive feedback to individuals using technology to pursue wellnessgoals.

The present disclosure contemplates that the entities responsible forthe collection, analysis, disclosure, transfer, storage, or other use ofsuch personal information data will comply with well-established privacypolicies and/or privacy practices. In particular, such entities shouldimplement and consistently use privacy policies and practices that aregenerally recognized as meeting or exceeding industry or governmentalrequirements for maintaining personal information data private andsecure. Such policies should be easily accessible by users, and shouldbe updated as the collection and/or use of data changes. Personalinformation from users should be collected for legitimate and reasonableuses of the entity and not shared or sold outside of those legitimateuses. Further, such collection/sharing should occur after receiving theinformed consent of the users. Additionally, such entities shouldconsider taking any needed steps for safeguarding and securing access tosuch personal information data and ensuring that others with access tothe personal information data adhere to their privacy policies andprocedures. Further, such entities can subject themselves to evaluationby third parties to certify their adherence to widely accepted privacypolicies and practices. In addition, policies and practices should beadapted for the particular types of personal information data beingcollected and/or accessed and adapted to applicable laws and standards,including jurisdiction-specific considerations. For instance, in theUnited States, collection of or access to certain health data may begoverned by federal and/or state laws, such as the Health InsurancePortability and Accountability Act (HIPAA), whereas health data in othercountries may be subject to other regulations and policies and should behandled accordingly. Hence different privacy practices should bemaintained for different personal data types in each country.

Despite the foregoing, the present disclosure also contemplatesembodiments in which users selectively block the use of, or access to,personal information data. That is, the present disclosure contemplatesthat hardware and/or software elements can be provided to prevent orblock access to such personal information data. For example, the presenttechnology can be configured to allow users to select to “opt in” or“opt out” of participation in the collection of personal informationdata during registration for services or anytime thereafter. In anotherexample, users can select not to provide certain types of user data. Inyet another example, users can select to limit the length of timeuser-specific data is maintained. In addition to providing “opt in” and“opt out” options, the present disclosure contemplates providingnotifications relating to the access or use of personal information. Forinstance, a user may be notified upon downloading an application (“app”)that their personal information data will be accessed and then remindedagain just before personal information data is accessed by the app.

Moreover, it is the intent of the present disclosure that personalinformation data should be managed and handled in a way to minimizerisks of unintentional or unauthorized access or use. Risk can beminimized by limiting the collection of data and deleting data once itis no longer needed. In addition, and when applicable, including incertain health related applications, data de-identification can be usedto protect a user's privacy. De-identification may be facilitated, whenappropriate, by removing specific identifiers (e.g., date of birth,etc.), controlling the amount or specificity of data stored (e.g.,collecting location data at a city level rather than at an addresslevel), controlling how data is stored (e.g., aggregating data acrossusers), and/or other methods.

Therefore, although the present disclosure broadly covers use ofinformation that may include personal information data to implement oneor more various disclosed embodiments, the present disclosure alsocontemplates that the various embodiments can also be implementedwithout the need for accessing personal information data. That is, thevarious embodiments of the present technology are not renderedinoperable due to the lack of all or a portion of such personalinformation data.

The foregoing is merely illustrative and various modifications can bemade to the described embodiments. The foregoing embodiments may beimplemented individually or in any combination.

The invention claimed is:
 1. An electronic device comprising: a displaythat includes an array of pixels and a lenticular lens film formed overthe array of pixels, wherein the display has a plurality ofindependently controllable viewing zones; a camera configured to captureimages; and control circuitry configured to determine eye positioninformation from the captured images, determine that a first viewingzone is occupied based on the eye position information, and modify abrightness level of at least one of the plurality of independentlycontrollable viewing zones based on the eye position information,wherein modifying the brightness level comprises increasing thebrightness level of the first viewing zone in response to determiningthat the first viewing zone is occupied, wherein a plurality ofunoccupied viewing zones is adjacent to the first viewing zone andwherein the control circuitry is configured to, after determining thatthe first viewing zone is occupied based on the eye positioninformation, set the brightness level of at least one of the pluralityof unoccupied viewing zones to full brightness and disable remainingviewing zones of the plurality of unoccupied viewing zones.
 2. Theelectronic device defined in claim 1, wherein the first viewing zonedisplays an image while the at least one of the plurality of unoccupiedviewing zones also displays the image.
 3. The electronic device definedin claim 1, wherein the display further comprises a louver film formedover the array of pixels.
 4. The electronic device defined in claim 3,wherein the louver film includes selectively opaque portions and whereinthe control circuitry is configured to control the opacity of theselectively opaque portions.
 5. The electronic device defined in claim4, wherein the control circuitry is configured to control the opacity ofthe selectively opaque portions based on the eye position information.6. An electronic device configured to be viewed by a viewer having afirst eye and a second eye, the electronic device comprising: a displaythat is configured to display three- dimensional content for the viewer,wherein the display has a plurality of zones that are each configured togenerate a respective image for a corresponding viewing area; a cameraconfigured to capture an image of the viewer; and control circuitryconfigured to: determine that a first viewing area includes the firsteye based on the captured image, wherein a first unoccupied viewing areais adjacent to the first viewing area; determine that a second viewingarea includes the second eye based on the captured image; set a firstnon-zero brightness level for the first viewing area; and set a secondnon-zero brightness level for the first unoccupied viewing area, whereinthe second non-zero brightness level is less than the first non-zerobrightness level.
 7. The electronic device defined in claim 6, whereinthe first viewing area has an associated first zone of the display,wherein the second viewing area has an associated second zone of thedisplay, and wherein the control circuitry is configured to: display animage with both the first zone and a third zone, wherein the third zonecorresponds to the first unoccupied viewing area.
 8. An electronicdevice comprising: a display that is configured to displaythree-dimensional content, wherein the display has a plurality of zonesthat are each configured to generate a respective image for acorresponding viewing area; a camera configured to capture an image; andcontrol circuitry configured to: identify an occupied viewing area basedon the captured image, wherein two or more unoccupied viewing areas areadjacent to the occupied viewing area; and based on a position of theoccupied viewing area, set non-zero brightness levels of the unoccupiedviewing areas that are adjacent to the occupied viewing area, whereinthe non-zero brightness levels of the unoccupied viewing areas decreasewith increasing separation from the occupied viewing area.
 9. Theelectronic device defined in claim 8, wherein the non-zero brightnesslevels of the unoccupied viewing areas decrease with increasingseparation from the occupied viewing area according to a gaussianprofile.
 10. The electronic device defined in claim 6, wherein thecontrol circuitry is further configured to: set a third non-zerobrightness level for a second unoccupied viewing area that is adjacentto the first unoccupied viewing area, wherein the first unoccupiedviewing aera is interposed between the first viewing area and the secondunoccupied viewing area, and wherein the third non-zero brightness levelis less than the second non-zero brightness level.
 11. An electronicdevice comprising: a display, wherein the display has a plurality ofzones that are each configured to generate a respective image for acorresponding viewing area; and control circuitry configured to:determine that a first viewing area includes an eye, wherein a firstunoccupied viewing area is adjacent to the first viewing area; set afirst non-zero brightness level for the first viewing area; and set asecond non-zero brightness level for the first unoccupied viewing area,wherein the second non-zero brightness level is less than the firstnon-zero brightness level.
 12. An electronic device comprising: adisplay that is configured to display three- dimensional content,wherein the display has a plurality of zones that are each configured togenerate a respective image for a corresponding viewing area; andcontrol circuitry configured to: identify an occupied viewing area,wherein two or more unoccupied viewing areas are adjacent to theoccupied viewing area; and based on a position of the occupied viewingarea, set non-zero brightness levels of the unoccupied viewing areasthat are adjacent to the occupied viewing area, wherein the non-zerobrightness levels of the unoccupied viewing areas decrease withincreasing separation from the occupied viewing area.